1. Field of the Invention
The present invention relates to a controller and a data storage device.
2. Description of the Related Art
In data storage devices such as a hard disk drive (HDD) and a solid state drive (SSD), the use state of a storage medium is managed by using various pieces of management information including a translation table. In the translation table, a logical address and a physical address of a storage medium are made to correspond to each other. In recent years, as the capacity of a data storage device increases, the size of management information tends to increase.
JP-A 2001-142774 (KOKAI) discloses a technique in which a part of a translation table stored in a non-volatile memory is read out as needed to a volatile memory and used. In the technique disclosed in JP-A 2001-142774 (KOKAI), reading out a part of the translation table from the non-volatile memory to the volatile table causes an overhead. Therefore, even though the size of the management information is increased, all of the management information needs to be stored in the volatile memory.
Because such a data storage device cannot function as a data storage device if the management information is lost, the management information needs to be stored in a storage medium at arbitrary timing. However, if the size of the management information is increased, it takes more time than before to store the management information. Furthermore, if all commands from a host device are interrupted while the management information is being stored, the performance significantly deteriorates.